The study was undertaken to estimate the economic impact of gastrointestinal parasitic infections in sheep. A total of 117 Madras Red sheep selected in different age groups like >3 years, 2 years and 1 year were used in this study. Egg per gram (EPG) of faeces and body weights of the animals were measured in monthly interval from the year 2012- 2014 at an organised sheep farm, Post graduate research institute of animal sciences (PGRIAS), Tamil Nadu Veterinary and Animal Sciences University, Kattupakkam, Chennai, Tamil Nadu, India. The estimation of economic loss due to gastrointestinal parasitic infections was calculated by accounting the difference in mean body weight gain, dressing percentage of sheep (40%), cost of treatment per sheep and market price (Rs.400/Kg) of meat in Tamil Nadu. The faecal examination results revealed that all the animals were positive for gastrointestinal nematode infection over the period. On coproculture, Haemonchus contortus was found to be the predominant species. The regression analysis showed that for every unit of EPG increase there was 0.008 kg loss in weight gain, ceteris paribus. The total economic loss was calculated was Rs.1194/ animal in the group of EPG 501-1000 and Rs.1674/ animal in the group of EPG >1000. This study shows that the gastrointestinal nematodes contribute for loss of weight in sheep, its leads to income loss to the farmers. The controlling of GI nematodes and keeping the better deworming practices in sheep is very much essential for increase the farmers income.
How to cite: Ilangopathy, M., Palavesam, A., Amaresan, S., & Muthusamy, R. (2019). Economic Impact of Gastrointestinal Nematodes in Sheep on Meat Production. International Journal of Livestock Research, 9(10), 44-48. doi: 10.5455/ijlr.20190331051814
In India livestock sector pay a vital role in improving the socio-economic conditions of rural masses. There are about 299.99 million bovines, 65.06 million sheep, 135.17 million goats and about 10.29 million pigs as per 19th Livestock Census in India (GOI, 2012). Small ruminants are the backbone of the livelihood of the rural farming community in majority of Indian states. In India goat and sheep contribute 16% and 7%, respectively among the overall meat production. The contribution of the livestock sectors to the national economy in terms of Gross Domestic Product is 4.1% at current prices for livestock sector during 2012 – 2013(M. M. Islam et al., 2016). Small ruminants suffer from many infectious diseases and heavy economic losses occur due to mortality as well as morbidity. Animal health economics is relatively a new discipline evolved to provide a quantitative insight into the economic impact of diseases in livestock (Dijkhuizen, 1992). Helminthic infections alone are responsible for 5 percent mortality and10 percent morbidity in sheep (Chakraborty and Lodh,1994). Gastrointestinal (GI) parasitic infections considered as one of the major constraints in small ruminants’ production. Prevalence of GI infection in sheep was one of the major constraints in the small ruminant husbandry in various regions of India (Kuchai et al., 2011; Manikkavasagan et al., 2013 and Singh et al., 2013).
Gastrointestinal nematodes cause severe economic loss in both sheep and goat production, especially the impact of gastrointestinal (GI) nematodes on sheep was very high. Clinical and sub-clinical infection with internal parasites reduces the productivity of small ruminant (Gall, 1981) and gastrointestinal helminth parasites are responsible for significant production losses in grazing ruminants throughout the world. Economic losses due to helminth infections in small ruminants are primarily due to reduced weight gain (Jas et al., 2007) and sub optimal productivity in large ruminants (Kumar, 2006). Since, reports estimating the economic losses due gastrointestinal nematodes in sheep are insufficient, this study was undertaken to determine the economic impact of naturally occurring gastrointestinal nematodes in terms of meat production in sheep in institutional sheep farm located at PGRIAS, Kattupakkam, Tamil Nadu, India.
Material and Methods
Study Area and Animal
The study was conducted from 2012 to 2014 on 117 Madras Red sheep natural infected with gastrointestinal nematodes GINs) at PGRIAS, Kattuppakkam. The sheep were maintained under semi intensive system and deworming was practiced once in three months. The sheep were selected in different age groups like >3 years, 2 years and 1 year and sheep were further categorized based on the faecal egg count such as EPG (<500, 501-1000 and >1000).
The economic loss due to GIN infection in sheep was estimated based on the reduction in body weight gain. The body weight of all the sheep were recorded at monthly interval, with the help of electronic weighing machine.
Faecal samples were collected per rectum at monthly interval. The eggs per gram (EPG) of faeces were determined by modified Mc-Master technique (MAFF 1989). The faecal samples were pooled and subjected to jar method of faecal culture.
Estimation of Losses
The total economic loss was calculated based on the main components such as differences in body weight, average eggs per gram of faeces (EPG), preventive cost and treatment cost. The cost estimation of mutton calculated based on the dressing percentage is 40% of the body weight for Madras red sheep.
The data were analysed by simple linear regression model and Pearson correlation co-efficient for relationship between body weight and eggs per gram of faeces (EPG) and One-way analysis of Variance (ANOVA) for comparing within groups using SPSS® version 20.0 for windows®
Results and Discussion
The present study revealed that H.contortus as the more predominant species in that farm based on the faecal examination.
Estimation of Economic Loss
The difference in final and initial body weight of individual animals were calculated. The economic loss was calculated based on the Rs.240/kg of meat after deducting the dressing percentage. The result of the weight gain was found to be negatively correlated with EPG and the co-efficient of correlation is –0.441 (P<0.001) (Table1). The co-efficient of linear regression model showed that EPG and weight gain are negatively associated and the causal relationship was found to be statistically negatively associated (p<0.001). Further the value of the regression co-efficient for EPG indicated that for every unit increase in EPG there would be 0.008 kg loss in weight gain, Ceteris paribus (Table 2). The value of the adjusted R2 was found to be 0.87, which indicated that 87.1% variation in weight gain in influenced by the EPG level.
Table 1: Relationship between EPG and weight gain
**Correlation is significant at the 0.01 level (2-tailed)
Table 2: Causal relationship between EPG and weight gain
|1||α (Constant||8.666 **||0.77||11.258||0|
|β (EPG)||-.008 **||0.001||-5.263||0|
Jas et al., 2007 conducted the economic loss study in two age group of goat and maintained as anthelmintic treated and infected in each age group and resulting economic loss for the two groups were Rs. 158.09 and Rs. 167.24. The anthelmintic treatment enhances the meat production by controlling the gastrointestinal infection based on the field study in sheep. The mean loss of body weight due to gastrointestinal nematodosis, as recorded, was 3.225 kg with a net per capita loss of 1.613 kg meat production in the infected group during the entire period of the study (12 months) (Jas et al., 2009). In the present study the economic loss was calculated over the period of natural infection of gastrointestinal nematode in Madras red sheep and changes in the body weight gain. Statistical analysis revealed the EPG 501-1000 range of animals were highly infected and the loss was calculated as Rs.1194/ animal and Rs.1674/ animal in the group of EPG-501-1000 and EPG >1000, respectively (Table 3; Table 4) during the entire period of study.
Table 3: The mean weight gains of each EPG group
|S. No.||Group||Mean ± SD|
Table 4: Economic loss due to GI parasitism in sheep
|Group||Average Loss Due to Reduced Weight Gain||Average Preventive Cost||Average Treatment Cost||Overall Loss|
This study has shown an economic loss of Rs.1194/ animal in the group of EPG 501-1000 and Rs.1674/ animal in the group of EPG >1000 over the study period. As well as every unit of EPG increases in animal, there was 0.008g of weight loss in sheep. So If animal having more EPG which leads to loss of body weight. Thus, this study shows gastrointestinal nematodes mainly affect the animal health as well as loss of farmers’ income. To maintain the better deworming practice and control of GI infection in sheep, that will help for better income generation by the farmers.
The authors thank the Indian Council of Agricultural Research; New Delhi for conducting this study under the research project entitled “All India Network Programme on Gastrointestinal Parasitism”. The authors also thank the faculty of PGRIAS, TANUAVS, Kattupakkam to permit this study in the station.